This invention relates to a valve in which the valve member which controls flow is electromagnetically operated. In a valve of this type the valve member, in addition to controlling flow, is also the armature for the solenoid or other electromagnetic means. Energization of the electromagnetic means results in movement of the valve member and a consequent opening or closing of a valve port. The valve member may be a free moving disc as shown, for example, in U.S. Pat. Nos. 1,302,511 and 3,498,330.
In one prior art valve of this type, a valve member is supported on three flat ended bosses. At least one of the bosses has a passage extending through it. When an electromagnet is energized, the valve member is raised off the bosses to provide a flow path through the passage in the boss.
One problem with this prior art valve is that it is difficult to seal against the flat end of the bosses particularly after a prolonged period of use. One reason is that contaminants inherently build up on the surfaces to prevent proper seating of the valve member on the bosses.